Insulation Resistance Test Using Megger; Pressure Test - Mitsubishi Electric FR-XC-18.5K-PWM Instruction Manual

Item
Input voltage Across terminals R2 and S2,
V S2 and T2, and T2 and R2
1
Input current Line current at terminal R2,
l S2, and T2
1
At terminals R2, S2, and T2,
Input power
and across terminals R2 and
P
1
S2, S2 and T2, and T2 and R2
Calculate after measuring input voltage, input current, and input power.
Input power factor
Pf
Pf =
1
1
Converter output voltage Across P/+ and N/-
Across terminals RES, SOF,
Input signal or LOH (+) and SD
(for sink logic)
Across terminals A and C
Fault signal
Across terminals B and C
5.2.1

Insulation resistance test using megger

• For the converter, conduct the insulation resistance test on the main circuit only as follows (use a 500 VDC megger), and
do not perform the test on the control circuit.
NOTE
• Before performing the insulation resistance test on the external circuit, disconnect the cables from all terminals of the
converter so that the test voltage is not applied to the converter.
• For the continuity test of the control circuit, use a tester (high resistance range), and do not use the megger or buzzer.
5.2.2

Pressure test

Do not conduct a pressure test. Deterioration may occur.
Measurement of main circuit voltages, currents, and powers
Measuring point Measuring instrument
Moving-iron AC voltmeter
Moving-iron AC ammeter
Electrodynamic single-phase
wattmeter
P
1
× 100%
×
3V l
1 1
Moving-coil type instrument
(such as tester)
Moving-coil type instrument
(Tester and such may be used,
with internal resistance 50 kΩ
or more.)
Moving-coil type instrument
(such as tester)
R2/L12
Power
S2/L22
supply
T2/L32
500 VDC
Converter
megger
Earth (ground)
PRECAUTIONS FOR MAINTENANCE AND INSPECTION
(reference measured value)
Commercial power,
within permissible AC voltage fluctuation (Refer
to page 156.)
P = W + W
1 11 12
(3-wattmeter method)
A measured value can be monitored on the PU.
Reference value: 1.35 × V
Maximum 380V (200V class) and 760V (400V
class) during the regenerative driving
Voltage when terminal is open:
20 to 30 VDC
Voltage when signal is ON: 1 V or less
Continuity test
Across A and C
[Normal] Discontinuity
[Fault] Continuity
P/+
N/-
Inverter
Remarks
+ W
13
1
Across B and C
Continuity
Discontinuity
153
5